Knitting method and machine



Dec. 10, 1946.

P. w. BRlsTovy- 2,412,248 KNITTING METHOD AND vMACHINE Filed oct. 12, 1941/ 5 sheets-sheet 1 I "fk"` :il /lg I /u/Wfsfow 1 y /Jwf w,

Dec. 10, 1946. P. w`. BRlsTow .2,412,248 y KNITTING METHOD AND MACHINE 3 Sheets-Sheet 2 Filed oct. 1 2, 1944 Dec. 10, 1946. P. w. BRlsTow KNITTIG METHOD AND MACHINE Filed 001'.. l2, 1944 3 SheetSV-Sheel; 3

Patented Dec. 10, 1946 KNITTING METHOD MACHINE Paul W. Bristow, Laconia, N. H., assignor to Scott & Williams, Incorporated, Laconia, N. H., a corporation of Massachusetts Application October 12, 1944, Serial No. 558,337

(Cl. (i6- 14) 19 Claims.

This invention relates to knitting machines of the type having superposed needle cylinders as shown, for example, in the patent to Bentley, 1313336, dated May 2l, 1929.

In machines of this type, the needles are under the control of sliders and are transferable to and from each needle cylinder to permit the knitting of a continuous fabric such as tubular fabric comprising courses some of the stitches of which are knitted with needles operating in one cylinder while other stitches are knitted by needles operating in the other cylinder. By shifting the needles from one cylinder to the other reverse concatenations of loops are effected to produce, when the shifts are frequent and elaborate patterns are produced, the fabrics which are commonly referred to as links-and-links fabrics. Such fabrics may have quite elaborate designs, such as diamonds or blocks, formed therein and may range to simpler patterns involving fairly continuous ribs, various patterns being the result merely of suitable control of the needle trans fers.

The broad object of the present invention is the provision of a knitting machine in which elaborate handling of the needles is made possible with particular insurance that no needle will ever be free of control in both cylinders, i. e., will not be released by both the sliders which are available for its control.

A further object of the invention is the provision of a machine of the type indicated in which tuck and oat stitches may be produced in the links-and-links fabric.

Still another object of the invention is to provide a knitting machine of the type indicated in which stockings may be produced, provision being made for reciprocatory knitting of heels and toes with the incidental narrowing and widening operations.

These and other objects of the invention, particularly relating to details of construction, will become apparent from the following description read in conjunction with the accompanying drawings, in which:

Figure l is a development of the cams for acting upon sliders, jacks and verges, various associated parts also being illustrated, Figure 1 encompassing these elements throughout one phase of the mechanism; l

Figure 2 is a section taken on the plane the trace of which is indicated at 2-2 in Figure 1;

Figure 3 is a perspective View showing Vcertain jack selecting elements;

Figure 4 is a section taken on Athe plane indicated at 4-4 in Figure 3; and

Figure 5 is a development, similar to Figure 1, but showing cams and associated parts particularly involved in a hosiery machine.

The machine to which the present invention is applied may have any number of feeds ranging from a single feed in the simplest case, for eX- ample in a hosiery machine, through two feeds which also may constitute a hosiery machine, up to a machine having quite a large number of feeds of the so-called body-knitting type. In the following description, reference will first -be made to a modification of the invention particularly adapted to a body machine in which no provision need be made for reciprocatory knitting, narrowing, or widening. In such a body machine, it may be assumed that there is present an even number of feeds grouped in pairs, a pair being herein described as involving a phase of operation. However, an underwear machine may have any desired number of feeds, from one upwards, between transfers. In this case two are shown, by way of example only. If only two feeds are involved, the phase would extend through 360 degrees and the end of a phase would then coincide with the beginning of the same phase. In the case of two phases, each would comprise degrees and they would be arranged in succession so that the end vof one would coincide with the beginning of the other. Obviously, such sequential arrangement can be carried on to a quite large number of phases as would be present in a large body machine. It will be evident that a description of one phase will suffice to cover any number of such duplicate phases.

Figure l shows in diagrammatic fashion the cams for control of the sliding elements, i. e., sliders, jacks and verges, for a single phase. Each phase comprises two feeds, the rst involving a stitch cam 2 arranged to control needles to take yarn from a feeding station indicated at 4 at which one or more yarn feeding fingers may be located, and the other involving a stitch cam 5 arranged for the control of needles to take yarn at a second feeding station indicated at 8 and at which similarly a number of yarn fingers may be provided. The stitch cams 2 and 6 may be axially adjustable for the control of length of stitches drawn thereat.

Beyond the stitch cam 2 there is located a cam lil serving to cause clearing of latches by loops which are drawn under ,the action of the stitch cam 2. This cam l0 is radially movable so that when withdrawn needles may ride at a tuck level.

movable, are adapted to eifect, when in inner position, rise of needles for purposes hereinafter described. A cam I8 is provided to effect trans'- fer of needles from the lower to theupper cyl-,

inder when the needles are partially raised by selective control means. A cam 20 serves to divide two raceways and serves to raise sliders in the lower cylinder which do not carry needles. A

cam 24 serves to lower sliders to insure engagement with stitch cam 6 even though, by virtue of adjustment, the stitch' cam occupies a position lower than that shown.- A ,similar cam 22 eifects the same function in conjunction with the stitch cam 2.

To guard against overrun of the lower sliders as they travel down the stitch cams 2 and 6, there are provided camsvZS and 28 which are vertically adjustable, respectively, along with the stitch cams 2 and 6. These cams also have rises as indicated to insure that the lower sliders properly engage the cams i4 Yand l2, respectively. Cams 30 and 32 are guard cams which segregate sliders controlling needles I3 through knitting waves from sliders which do not carry needles. Cams-34 and 36 serve to lower sliders in the lower cylinder which do not carry needles to avoid interference with the formation of stitches by needles in the upper cylinder which pass through knitting waves adjacent the positions of these cams.

The cams associated with the upper cylinder include the stitch cams 38 and 40 associated, respectively, with the first and second feeding stations. Cams 42 and 44 associated, respectively, with cams 46 and 48 serve to lower upper sliders to cause needles carried by them to clear their loops. Cams 58 and 52 are arranged to raise uppei` sliders to present them for proper engage- `ment by the stitch cams 38 and 46, these latter being axially adjustable for the purpose of Controlling the lengths of loops knitted by needles in the upper cylinder. Cams 54 and 56 operate alternatively with the cams 42 and 44, cam 54 being joined by a toggle connection with cam 42 and cam 56 being joined by a similar toggle connection with the cam 44. By this arrangement only one of cams 42 and 54 is in operation at the same time, while the same is true of the pair of cams 44 and 56.

Guard cams 58 and 88 are connected to the `same blocks as stitch cams 38 and 40 so as to be axially adjustable therewith. They prevent overrun of the needles when they are moved for stitch drawing and also serve by their rises to insure proper engagement of the upper sliders with the cams 42 and 44 following a stitch drawing operation despite extreme adjustment of cams 38 and 40 to draw extra long stitches.

A cam 62 serves to lower upper sliders to effect transfer of needles from the upper cylinder to the lower cylinder while cam 64 serves to restore the upper sliders to a normal level after the transfer of needles therefrom, at which normal level they may again receive needles transferred from the lower cylinder.

The lower and upper sliders which permanently remain in their respective cylinders are indicated diagrammatically at the right of Figure 1. The lower sliders 66 are provided with butts 68 and l0 which, together, by cooperation of the cams, serve to control the movements of the lower sliders. rIhe lower sliders are provided with hooks 12 engageable in conventional fashion with the lower hooks of the double hook needles 13 to serve to control their movements.

The upper sliders i4 are similarly provided with pairs of butts 16 and 'I8 which, by cooperation with the cams related to the upper cylinder, serve for their control. These upper sliders are provided with hooks engageable with the upper hooks of the needles to actuate them when` 'the lower hooks are operating to handle the yarn.

A cam 82 in the needle transfer region operates in conventional fashion to tilt the sliders to disengage their hooks from the respective needles, as indicated in Figure 2t The action is a conventional one such as described in Houseman K Patent No. 2,252,769. v

Below the lower sliders are located jacks H6 which are acted upon by a series of controlling cams which will now be described.

These jacks ||6 are provided with upper butts H8, saw-tooth butts H9, and lower butts |26 which are provided with undercuts indicated at |22 adapted to be engaged by the sharpened edges of suitable cams. Among the cams cooperating with these butts are 84, 86, and 88. In advance of the cam 84 there are selectively inwardly movable cams adapted to be engaged by the saw-tooth butts ||9. Asimilar group of cams 92 is located in advance of cam 86 while a further similar group of cams 94 is located in advance of the cam 88. Adjacent the groups of cams 90, 92, and S4 are cams 96, 98, and |00, respectively, arranged to engage the outer surfaces of the butts |20 for the purpose of moving these butts inwardly to cause them to avoid engagement with the cams 84, 86, and 88. Cams |02 and |04 are provided with sharpened edges and serve to engage the undercuts |22 of lower sliders which have been pressed inwardly to elfect outward movement of the lower ends of these4 jacks to present them for action of the next selective cams upon their saw-tooth butts, and also to present their butts for possibleengagement by the respective cams 98 and |00. Cams |06 and 68 are provided for action upon the upper butts ||8 of jacks which are raisedby cams 84 and 86. Cam H2 defines a raceway through which b-utts H8 ride when jacks are raised by the cam 88. The cam ||2 is provided with a portion l|4 designed to engage butts 8 Vand lower slightly jacks which are not engaged by the cam 88. A

cam I|0 serves to lower jacks which were raised by cam 88. Cams |24 and |26 are guard cams which carry additional cams |28 -and |30 which act upon the butts ||8 of jacks which have not been raised respectively by cams 84 and 86 to insure that these jacks remain in the cylinder slots when the gaps in the vicinity of cams |06 and |68 are reached. A cam |32 serves as aguard cam to define the extent to which butts I8 are lowered bythe action of cam l I4. Y

Various other cams are provided, as indicated in Figure 1, which need no special mention, being provided either to prevent overrun of sliders in the event their friction inthe cylinder slots is insuincient or to insure movementsv by acting upon the Second Suder butt in the event thefbutt which normally should dene the slider movement 15 breaks. The functions of such auxiliary cams will be evident from the drawings.

Additionally certain -carns perform the function of holding the sliders and jacks in their slots and prevent tilting when that is to be avoided.

Referring to Figure 2, the upper cylinder is indicated at 99 and the lower cylinder at IDI. These cylinders are provided with the usual slots for reception of the sliders, needles and jacks, the slots being defined by walls, preferably of the inserted type. The lower portions of the walls in the upper cylinder are axially slidable to provide verges It, the lower ends m of which serve to hold the yarn between loops when stitches are being drawn by needles in the upper cylinder. 'I'hese verges are provided with butts 'I 01 adapted to be acted upon by cams as hereafter described. Conventional arcuate sinkers |09 are provided, controlled in the usual fashion by cams, to cooperate with needles in the lower cylinder during stitch formation.

In Figure l, there are illustrated all of the possible paths which may be taken by the butts of the upper and lower sliders for the production of the several results of which the machine is capable. As will be evident from that figure, 'the motions of the sliders are, in general, dened in each passage through the illustrated cams by the actions of the cams on both upper and lower butts; i. e., in a single passage, the motion of a slider might be defined first by action upon a lower butt, then by action upon an upper butt, followed by further action upon a lower butt, and so on. In the figure, the parallel paths of both the upper and lower butts are illustrated, and the complete path Imay be ascertained by considering the suc-V cessive actions of the various cams on the butts. The passage of sliders from the right-hand to the left-hand side of the figure will, for convenience, and as pointed out above, be referred'to as a phase of operation.

As has been indicated, in a two-feed machine this phase of operation may extend through 360 degrees, so that the sliders leaving the left-hand side of the figure may be considered as immediately reappearing at the right-hand side. On the other hand, as is more usual in underwear machines, the complete circumference of the machine may involve a relatively large number of such phases in which the cams may be quite different.

In any event, the lower sliders may enter a phase along two alternative paths, A and B. Similarly, the upper sliders may enter the phase along two alternative paths, J and L. Beyond this entrance, the paths may be variously split up in fashions which will be best understood by reference to particular events occurring in the phase.

First, there may be considered the operations in the lower cylinder giving rise to normal stitch formation at both feeds. If a lower slider carrying a needle enters at A, or if, as will be pointed out, shortly after entry a needle is transferred thereto from the upper cylinder, the slider in knitting will follow the successive paths C, F and A, so as to enter the next phase (or re-enter the same phase in a two-feed machine) on the path A. In this case, the slider is first slightly depressed at 22, depressed fully, so that its needle will seize yarn, by the cam 2, raised slightly by cam 25 and then by the cam I4, if cam It is in active position, then further raised either by its jack, as hereafter described, or by the cam Il] if that .cam is in active position, depressed slightly CII 6 at 24, fullydepressed at the second feed by the cam E to take yarn, and then raised, following a slight rise at cam 2S, either by the cam I2 or by its jack as hereafter described. In the paths F and A, the latches are cleared.

If a tuck stitch is to be produced by failure of a needle to clear -its latch before taking yarn at the rst feed station 4, the slider may in a previous'phase approach the cam 2 along either of the alternate paths A, C or B, D. After being lowered by the stitch cam 2, it will `be raised by the cam I4, and then further raised to the' path F either by the cam vIll or by action of its jack. rIhis clears the stitch completed at the first feed. It will then be lowered by the cam 6, but under this condition cam 'I2 is withdrawn so that it leaves the phase along the path B. As will be evident from consideration of the phase, entry into the next similar following phase along the path B cannot lead to a rise to the latch-clearing level at C but rather, the rise will only occur under the action of the cam I5 to the path D in the approach to stitch cam 2. Consequently, yarn is again taken at the rst feed of this following phase without .clearing of the loop which was taken at the second feed. Tucking will, therefore, occur. As will be apparent hereafter, yarn in this following phase may be taken only at the second feed point, in which case the Acam i5 will be withdrawn so that the path E will be the continuation of the path B. Very complicated tucking at successive feeds is possible, but this need no-t be described in the present analysis.

Al third alternative involves production of a tuck stitch by failure of a needle to clear its latch before taking yarn at the second feed point. In this case, as before, entry into the phase may occur either along the path A, C or the path B, D, followed by lowering of the sliders by the stitch cam 2 for the seizure of yarn at the first feed point. The sliders are then raised by the cam I4, but in this case, the cam Ill will be withdrawn and the slider will not be raised by its jack, with ie result that it 'will follow the path G which is insufficiently high to cause latch-clearing. The loop of yarn from the i-lrst feed point is, therefore, carried in the hook along with the -yarn seized at the second feed point by the action of the stitch cam 6 and is cleared by the subsequent rise of the slider over the cam l2, or by the action of its jack, to the path A.

Multiple tuck stitches may be produced by entry of the slider along the path B, D, and depression by the stitch cani 2 to take yarn at the first feedr the jack. Yarn is then taken at the Second feedv point under the action of the stitch cam E. The slider may then rise up cam l2 if this cam is in active position or travel up, by action of its jack, to path A; or, on the other hand, it may remain in path B so that in the next phase, the stitch may be cleared with rise of the needle to the latch-clearing level either at the first or second feed, it being possible to take yarn again at the first feed or to pass this feed without taking yarn under the float conditions hereafter described.

To produce a draw stitch at the first feed, the slider must enter on the path B and then follow the path E, resulting from the withdrawal of the cam I B. If yarn is to be taken at the second feed either for forming a tuck or a normal stitch, the slider then rises over cam It to follow the path G or over both vcam M and then, by the .action of cam I0 or by jack action, to the path F.

' To produce azdraw stitch at the' second feed, cam I4 isA withdrawn so that afterpassing'the position of the stitch cam 2 the slider will follow the path H. If. a stitch in the phase is to be made with the yarn at the first feed, clearing of the latch by the loop of this yarn is then effected by rise of the slider to the path A either by the action of the cam I2 or rise of the jacks.

The above describes in a general way the possible alternative actions of needles controlled by sliders in the lower cylinder in a single phase. It will be evident, however, that the ultimate stitch formation in the fabric may depend, in certain instances, on what has occurred in the preceding and succeeding phases, and, in fact, several instances of that have been heretofore indicated. It is possible, therefore, that quite complicated stitch arrangements may be produced.

One further action of the slider in a phase may take place attending transfer of a needle from a lower slider to the corresponding upper slider. This will be more fully described hereafter, .but it will suffice to point out at the Present time that in this case the lower slider enters at A eithei` carrying the needle to be transferred or empty, the latter along the shaded portion of the path A. When the unshaded portion of the path is reached, the needle is transferred from the upper cylinder to the slider, but in then following the path O the needle is transferred or retransferred to the upper cylinder, the rise being effected by jack action and the cam l. Beyond the cam I8 the path O is followed by the empty slider with depressions at 3d and 36 for the purpose of getting the slider out of position to interfere with the needle latch when the needle is raised in the upper cylinder by cams S8 and dll and the latch is closing upon the seized yarn. If the empty lower slider continued to follow a path at a higher level it would be in the path of swing of the latch and would interfere with yarn seizure.

The upper sliders also have alternative paths for the production of different stitches and for effecting transfer. If knitting at both feeds is to occur, the upper slider, which may or may not carry a needle, will enter along the path L and will be depressed by the cam G2. If, at this time, it carries a needle, the needle will be transferred to the lower slider so that through the shaded portion of the paththe upper slider will not carry a needle. When the position in line with the cam I8 is reached, however, and if the corresponding lower slider is raised over cam i8, the upper slider will thereafter carry a needle and will be raised successively by the cam 50 and the stitch cam 33 at the first feed to take yarn thereat. It will then be advanced by the cams 42 and 46 along the path M to a level serving to clear the latch. Following this, it is again raised by the cams 52 and d0 to take yarn at the second feed and is advanced by the cams d4 and 48 to follow the path N to effect clearing of the latch. Thus stitches are completed at both the feeds and entry into the next phase takes place along the path L. l

if knitting is to occur at the first feed `and a draw stitch is to be produced at the second, the path is as just described past the stitch cam 3%. In this case, however, the cam 42 is Withdrawn so that the path K is followed. The cam 4d, however, remains in action So that the slider is advanced by the cams 4d and 48 along the path N to effectv clearing of the stitch. This clearing may, however, be delayed until a subsequent phase, by withdrawal of the cam 44 in which case the path J will be followed.

If a draw stitch isto-be produced at the rst feed and knitting is to occur et the secondfeed, the slider must enter the Vphase along: the path J, when transfer ofi-its needle to the lower cylinder will not occur and under which condition it'v will not cause seizure of the yarn at the rst feed,being only slightly raised by the stitch cam and then slightlyre-advanced by the cam 58 to engage the camV d2 now in action which, togetherwith carnll, will cause it -to follow the path M.

It irs-then raised by camsEZ` and 40 to take yarn` at-the second feed followingl which it will take I the path N, if cam 44 is active, in order to clear the latch or, alternatively, the path J if the cam 44 is withdrawn,withideferring of latchclearing until the next phase.

Draw stitches will be produced at both feeds if cams 42 and 44 are both withdrawn, in which case the path will be J, K, J. Y

It may be noted that all of the various paths just described may-be followed not only by sliders rwhich carry needlesybut by empty sliders to which needles are not transferred at the position of cam- ES. Such empty sliders may thus go along with sliders carrying needles in the upper cylinder without having any effect.

The transfer of all needles entering along path L from the upper cylinder to the lower cylinder by cam 62- is a necessary event if patterns of links-and-links type are to be produced, or if changes from one type of rib structure to another are to be made. However, where a considerable length of fabric is to be produced without a change in the rib arrangement, as, forexample, a 1X1 rib top or a broad rib leg, it is not necessary to produce transfers of needles in each course. In such case, once the desired needle arrangement is secured, cam 62 may be withdrawn so that the sliders pass it atthel level of path L, thereafter going through any of the various waves described above. time, of course, jack selection of the lower sliders for transfer is interrupted, or cam I8 may be withdrawn.

The action of jacks has been so far merely indicated. The jacks perform three different functions: namely, that of effecting selective transfer of needles from lower to'upper sliders, that of providing selection as an alternative to the action of cam I0, and that of providing selection as an alternative to the action of the cam I2. The various possible paths of the jacks will now be described.

As in the case of the sliders, the paths taken by the jacks are Vdetermined by the actions of cams upon both upper butts H8 and the lower undercut butts |20. The parallel paths of these butts are indicated in Figure 1, the path of the lower butt having its lower edge shown as corresponding to the throat of the undercut at I22.

The jacks enter the phase of operation described along either of the alternative paths P and Q. The former results from the depression of ajack under the action of cam IIB. The latter results from the depression of a jack by the action of the face II4 of the cam II2. As will be evident from the drawings, the two paths differ only in that the path Q is slightly lower than the path P.

If, following the path P, one of the cams 9U engages a saw-tooth butt II9 of a jack, the butt IIlV thereof will be raised sufciently to clear the cam 98 so that the lower end of the .jack will not be .rocked inwardly thereby and will conse- At the same,

quently be in such position that its undercut |22' will engage the edge of the cam 84 so that it, will be raised along'fthe path R, being subse quently depressed by the action of cam Hlon its butt H8. At the top of the rise along the path R, it will serve to elevate a needle from the path A through the initial part of the path O so that the needle will be thereafter raised by the cam I3 to transfer position.

If, on the other hand, a jack following the path P is not raised by the action of a cam 9i) on one of its saw-tooth butts, its butt |29 will not be raised sufficiently to clear the cam 9 with the result that the jack will be rocked inwardly and will, therefore, fail to engage the cam 84, thus following the path indicated at S. Upon reaching the cam H32, the undercut l22 of its butt l2@ which will be in a radially inner position will beV engaged by the cam H32 so that the lower end of the jack will be rocked outwardly for a` sub-- sequent action hereafter described (see the first jack from the left in Fig. 3).

If the jack enters the phase along the path Q, there are two possible operations which may occur. First is the normal intended one in which none ofthe cams B9 will engage any saw-tooth butt. Under such circumstances, the jack will not be raised from the path Q and will follow one butt position below the path` S, having its lower end rocked inwardly by the cam 9S and being later picked up bythe cam m2 which will slightly raise it to the indicated path S and also move outwardly its lower end. If, however, in entering along the path Q one of the saw-tooth butts is engaged by a cam 90, the jack will be raised by the cam. The rise imparted by the cam 9E) is only the same as the lowering action elected by the surface lill of the cam H2, and inasmuch as the path Q is already below the path P by the amount of this rise, the rise so resulting will not effect the missingv of the cam 96 by the butt Z, in fact, leaving the jack in the same position as would occur if it entered along the path P and was not raised by a cam 52%. Consequently, it will follow the path S as previouslydescribed, if it entered along path P but was notJ raised by a cam Sil.

The action of the cams lll and |82 result in the paths R and S being merged vbefore the jacks reach a position for action by the cams 92. All of the jacks are in position for engagement by the cams 92, their lower ends being positioned outwardly by reason of the action of cam H32. By the selective action of cams 92, therefore, certain of the jacks may be slightly raised to miss the cam Q8 and accordingly follow the path T' over the cam 85, being subsequently depressed by the cam lila. As a result of this rise, the needles are positioned as if raised by the cam lli, regardless of whether that cam is in or out, to the path F previously described. If a jack is not raised by one of the cams 92, its butt E25' will be rocked inwardly by the action of cam 98 (see the third jack in Figure 3) and, consequently, it will follow the path U, being engaged by the cam 94 having an action similar to that of cam m2, namely, positioning the lower'end of the jack outwardly for another selecting action. As will be evident'from Figure l. the paths 'I'.andU merge at the position of the cam lila. AAccord-- ingly, all of the jacks are presented under-the' same conditionsv to the next selecting action by cams 94.

If a saw-tooth Vbutt of .lack is engaged by a cam 94, the jack will. be raised so that its'butt IZB will clear the cam Iil andV consequently itv will followr the path V over the cam 38 after which it will be depressed by the cam ll to the path` P.. In the rise over the cam 88, its corresponding needle will be raised so that even if the cam I2 is withdrawn, it will, by engagement with` the cam i3, be brought to the path A.

If no cam dll engages a butt of a jack, the jack will. be rocked inwardly by the action of cam on its butt |20 with the result that it will miss the cam 88 and will follow the path W. Upon reaching the face H4 of the cam H2, the jack will bel slightly lowered and thereafter follow the path Q previously described.

, The butts IUT of the verges Ill3A follow the path X which involves depressions by cams 3S) and el respectively followed by rises over cams 43 and 45. The wavesV thus given to the verges correspond to the positions at which stitches are drawn by needles in the upper cylinder, The verges serve to measure the stitches by engagement of yarn between adjacent needles in the upper cylinder, their use being specially pronounced when a series of successive needles are knitting in the upper cylinder and so have interposed no needles in the lower cylinder to hold the yarn downwardly.

It will be evident that a lower slider which has transferred its needle to an upper slider in rising over` cam I3 must follow the path above cams I8, 22, 2, 3G, 29, 6, 32 and i3, so as to enter the phase at A and cannot possibly getinto the path B. As a result, it must be in position to receive a needle transferred from the upper cylinder at cam 552. This is of major` importance since, if an empty lower slider were in path B when passing the transfer position, the corresponding upper slider would release the needle without its being received by the lower slider. Once so released, itis unlikely that the needle will be reengaged by either slider, resulting in a load up that will cause the needle or slider to break, or if the needle hook is contacted by a slider, the slider cannot move outwardly and breakage of occur. The invention denitely insures that no needle can ever become out of control by both sliders.` If, due to some miscalculation of the pattern set-up, `a lower slider fails to. transfer its needle to an upper slider when it should do so, noy damage, eXcept to produce an undesired pattern, will result, since the needlewill remain under control of the slider though it follows an incorrect cycle.

The fact that the described path above the cams is necessarily followed by any lower slider which carries no needle means that so far as selection is concerned, it is possible to disregard any past performance of a slider and take into account only whatis Ato be accomplished therev after. Otherwise, if an empty lower slider could follow oneof the knitting paths, it would be necessary to insure its selection by one of the cams 94 to be sure (when cam l2 is withdrawn) that it could not enter the phase at B.

The foregoing is obviously of advantage to the xer in that the pattern may be laid out in adirect fashion without, keeping in mindvthe patterning in a preceding course. Thel safety racewayis necessary if there is any mixup of selection at the lap in the .back of a stocking caused when the selecting cams change.

In the modification of Figurey 5, which represents the application of the invention to a hosiery machine capable of knitting heels and toes, the

l either the. needle hooi; or the'slider hook will rst feed is represented at |38 and may comprise a conventional series of yarn feeding fingers. Associated with this isa latch guard plate |39, the purpose of which is hereafter described.

At the lmain feed there are two stitch cams |60 and |42 similar in construction butA adapted for alternative functioning, the upper acting upon the upper butts of the sliders in the lower cylinder during the major round-and-round knitting operations, while the lower acts upon the lower butts of such sliders during the forward reciprocations in the formation of heels and toes. A` center cam |44, acting on upper butts, funci tions in conjunction with the cams |40 and |42 and additionally in conjunction with the reverse stitch cam |46. Guard cams |43 and |41 are provided to limit the downward movements of sliders as they are lowered by the stitch cams.

Cam |88 is provided to act upon lower butts of sliders for a purpose hereafter described. Cams |50, |542, and |54 are provided to cooperate with each other in raising sliders lowered by the forward stitch cams to provide alternative clearing of loops when in active position or the production of tuck or draw stitches Vby jacks when the cams are inactive. A cam |56 serves to lower sliders as hereafter described.

The second feed point is indicated at |58 and may comprise a series of yarn feeding fingers associated with cams |60 and |62 which serve to bring the needles down to draw stitches. A' guard cam |68 prevents overrun of sliders in the caseof stitch formation at the second feed. VCam |63 brings selected sliders to a position to present their needles for wrapping, this cam following a slider selecting means of the type indicated in Figure 1, which, however, is not indicated inA this ligure except by the indication of the vpath taken by the sliders when selection occurs. `Cams |96y and |68 serve to raise sliders for purposes hereafter described. l

Cam |10 serves for the raising of lower sliders to a transfer position following selection as in the modification of Figure 1 by selecting means not shown in the present modification. Cam |12 following cam |10 serves to re-lower the raised sliders which have delivered their needles to sliders in the upper cylinder. An auxiliary safety cam is provided to effect the same action as cam |12 if a lower butt is broken. Cam `|16 serves to raise lower sliders to a tuck level prior to the first feed point. Cam |18 serves to raise sliders as hereafter described during reverse reciprocation.

Cams |86 and |82, operating upon upper sliders, effect the transfer of needles from the upper cylinder to the lower cylinder and the return of the sliders. Cam |86 acts upon sliders during the transfer operation to free their hooks from the needle hooks. Cams |86 and |88 serve top-Dresent the needles carried by the upper cylinder to the first feed stitch cam |90, with which cooperates a guard cam |9| to avoid overrun of the upper sliders. Cams |92 and |93 serve to lower the upper sliders to effect latch clearing. Cams |95, |96, and |91 present the upper sliders to the stitch cam |98 at the second feed with which there is associated a guard cam |99 to prevent overrun of the sliders. Cams 200 `and 202 following the second feed, lower the upper sliders and effect clearing of latches of the needles in the upper cylinder.

The usual raising pickers 204 and 206 blank the cams of the main feed as indicated. A lowering picker 208 normally occupies an upper inactive position except when widening takes place, whereupon it is lowered into active position, the inactive position being illustrated in Figure 5.

In addition to the cams described, there are others not requiring specific mention but which act as safety cams to avoid damage in case of butt breakage, to prevent overrun of sliders, or to maintain sliders in the cylinder slots.

The sliders in the case of this modification are similar to those of Figure 1, but in this case the lower sliders are differentiated into two groups by having long and short butts, respectively. Y The sliders controlling instep needles are provided with short lower butts and long upper butts, while those controlling sole needles are provided with long lower butts and short upper butts'so that diiferentiation of the two groups may be effected by partial lwithdrawal of cams as described below. The sliders are associated with jacks as in the mod ication of Figure 1.

Knitting'a-t both feeds during rotary knitting may be accomplished in both the lower and upper cylinders. In such case, a lower slider may enter along any of the three paths A', B', or O. In case of entry along paths O' or B', the slider will ride over cams |66 and |08 to follow the. path D. In the case of entry at A', it will also follow D', which is in the direct line of A'. After depression by center cam |44, it will then be depressed by stitch cam |410 along the path F' taking yarn at the feed station |39. Thereupon it will ride over cams |50, |52, and |54 to the latchclearing level G' passing then beneath cam and stitch cam |62 to J', taking yarn at the second feed station |58. Following this, it may. continue on the path B or, alternatively, be raised at K' by the action of suitable wrap selection mechanism on its corresponding jack in the event that the needle'is to be wrapped. After being raised by cam |63 to the level at which wrapping will take place, it will re-enter the phase of knitting at O'. kLatch clearing by theY stitches Vdrawn at the second feed is occasioned by the cam |68, wrapping taking place at tuck level. l

In the case of sliders in the upper cylinder, they enter the phase at P', pass beneath thecam |80 to transfer their needles to the cylinder sliders, then rise over cam |62 beyond which needles are transferred to upper sliderswhich are to control the taking of yarn. The sliders then pass over cam 86 by which they are brought to a level such that their needle latches are positioned to be held open by the latch guard plate |39. They then rise over the stitch cam |90, taking yarn at the rst feed. Depression of the upper sliders then occurs under the action of cams |92 and |93, the` needles being lowered by the latter to a latch clearing position. They then rise over cam |94, pass above cam |96, and then rise over lstitch cam |98 taking yarn at thesecond feed. They are then lowered by cams 200 and 202, the latter effecting clearing of the latches and bringing them back to the path P.

Tucking may be effected at the iirst feed by needles controlled in the lower cylinder if cam |66 is withdrawn, with the result that the sliders follow the path B', L' rather than path B', D moving at the tucking level as contrasted with D' whichis at the latch clearing level. AThe remaining path will be the same as that involved in knitting at the second feed, clearance of both stitches occurringl as passage over the cam' |54 conditions are again similar to that involved in knitting at both feeds with the exception that cam |54 is now withdrawn and rise of the lower sliders first occurs, after the yarn is taken, by passing over cam |50 along the path H where.u by the needles are raised to a tuck level. Provision is not made in the set-up illustrated fo-r tucking in the upper cylinder.

Draw stitches may be produced at thenrst feed in the lower and upper cylinders; If this is to occury at the rst feed in the lower cylinder, cams |56 Vand |16 are both withdrawn so that the lower sliders follow the Successive paths B and M passing below the stitch cam Mil at the rst feed. Thereafter by the action of cams |50,- |52, and |54, they are raised to the latch clearing level at Gand are ready to pass through the stitch drawing wave at the second feed.

In case draw stitches are to be pro-duced in the upper cylinder at the rst feed cam 200 is withdrawn, in which case, after leaving the stitch cam |98 at the second feed, the upper sliders will follow the path Q', thereby passing above the stitch cam |91).

If selective formation of draw stitches is to occur at the second feed in the case of lower cylinder needles, cam |50 is withdrawn so that the lower sliders, after leaving the stitch cam |40, will follow the path I', J', if not raised by jacks, below the stitch cam |52 thereafter following either the path K', O' or the path B previously described, the former being followed if wrapping is to occur.

If non-selective draw stitch production is to occur in the upper cylinder at the second feed, cam |92 is withdrawn so that the upper sliders, after passing the stitch cam |90, will follow the path R' above the stitch cam |98, missing the yarn at the second feed. Thereafter these; sliders are again engaged by cams 2d@ and 262 to follow the path P.

As has been previously indicated, the sliders which carry instep needles are provided with short lower butts. If the cam llt is Withdrawn to miss all butts and cams ISG and |78 are partially withdrawn so as to engage long' butts but miss short butts, thev short butt instep sliders will reciprocate in the path made up of M', I', J and B. The needles carried by these sliders accordingly fail to engage any yarn at either feed, holding lops during the formation of the heel and toe for resumption of the knitting of the instep or the loopers rounds. The long lower butt sliders, on the other hand, will, in a forward reciprocation, follow substantially the normal knitting path involved inknitting yarn at the first feed. However, in this case, the stitch cam |40 is raised so that the alternative stitch cam |42 acting on lower butts cornes into action. and controls the wave involved inthe seizure of yarn. The path in a forward reciprocation is then A', D', F', G', cams i5!! and |54 raising the sliders, after knitting, to latch` clearing level.

In a reverse reciprocation, the long butt sliders will enter the phase from the left at the level of path A', will pass withdrawn cam |50, 'will ride over stitch cam |42, will be lowered by center cam |44 to ride down the stitch cam lli@ taking yarn at the rst feed, and will then ride over the. cam |18 to a latch clearing level.

This action occurs for ally except the picked sliders which, on each reciprocation during'a narrowing operation, will be those which precede the group of long lower butt sliders. The action of the pickers is'to. raise the-slidersto they level of the path N at which level the picked up sliders will ride past the withdrawn cams |14 and |56 in both directions of reciprocation. Inl the subsequent widening operation, this same picking occurs with the additional picking vdown of two needles upon each reciprocation inthe usual fashion by the lowering picker 20B which will effect lowering of the sliders to the active levels.

With respect to avoidance of possible loss of control of a needle by both of its sliders, the action of the arrangement of Fig. 5 is similar to that of Fig. l. A lower slider, which transfers a needle to the upper cylinder by jack selection power to cam ile followed by a transferring rise over that cam is constrained to follow a path below cams |l| and |72 (and above the guard cam lf3) above cam |44, under VM, over |43, above guard cam |49, and under iet, leaving the phase along the path A which insures its location in position to receive any needle transferred from the upper cylinder. It cannot possibly get into the path B which is followed by sliders controlling needles for various operations as described above. Even with an error in the set-up of the patterning controls, therefore, it is impossible for an empty lower slider to get out of needle receiving position at the transfer point.

What I claim and desire to protect by Letters Patent is:

1. A knitting machine comprising superposed needle carriers, sliders provided with butts and needles controlled by the sliders movable in said carriers, means for transferring all needles located in one carrier to the other carrier, means for thereafter transferring selected needles from the second carrier to the first carrier, rneansfor controlling sliders in the second carrier to cause needles therein to form selectively stitches of varying types, and means for preventing sliders which have transferred needles to the rlrst carrier from-being controlled by said means for causing the formation of stitches.

2. A. knitting machine comprising superposed needle carriers, sliders provided with butts and needles controlled by the sliders movable in said carriers, means for transferring all needles located in one carrier to the other carrier, means'for thereafter transferring selected needles from the second carrier to the first carrier, means for controlling sliders in the second carrier to cause needles therein to form selectively stitches of varying types, and means for preventing sliders which have transferred needles to the first carrier from being controlled by said means forcausing the formation of stitches, thus positioning said last named-sliders to receive needles from the other carrier in a subsequent phase of knitting.

3. A knitting machine comprising superposed needle carriers', sliders provided with butts and needles controlled by the sliders movable in said carriers, means for transferring all needles located in one carrier to the other carrier, means for thereafter transferring selected needles from the second carrier to the first carrier, means for controlling sliders in the second carrier to cause needles therein to form selectively stitches of varying types, and means for preventing sliders which have transferred needles to the first carrier from being controlled by said means for causing the formation of stitches until they have again become associated with needles.

fl. A knitting machine comprising superposed needle carriers, sliders provided with butts. and needles controlled by the sliders. movable in said carriers', means for transferring all needles located in one carrier to the other carrier, means for thereafter transferring selected needles from the second carrier to the rst carrier, means for controliing sliders in the second carrier to cause needles therein to form selectively stitches of varying types, and means appurtenant to each of two feeding stations for preventing sliders which have transferred needles to the first carrier from being controlled by said means for causing the formation of stitches.

5. A knitting machine comprising superposed needle carriers, sliders provided with butts and needles controlled by the sliders movable in said carriers, means for transferring all needles located in one. carrier to the other carrier, means for thereafter transferring selected needles from the second carrier to the first carrier, means for controlling sliders in the second carrier to cause needles therein to form stitches, and means for presenting sliders which have transferred needles to the first carrier from being controlled by said means for causing the formation of stitches.

6. A knitting machine comprising superposed needle carriers, sliders provided with butts and needles controlled by the sliders movable in said carriers, means for transferring all needles located in one carrier to the other carrier, means for thereafter transferring selected needles from the second carrier to the first carrier, means for controlling sliders in the second carrier to cav-.se needles therein to form stitches, and means for preventing sliders which have transferred needles to the first carrier from being controlled by means for causing the formation of stitches, thus positioning said last named sliders to receive needles from'the other carrier in a subsequent phase of knitting.

7. A knitting machine comprising superposed needle carriers, sliders provided with butts and needles controlled by the sliders movable in said carriers, means for transferring all needles located in one carrier to the other carrier, means for thereafter transferring selected needles from the second carrier to the first carrier, means for controlling sliders in the second carrier to cause needles therein to form stitches, and means for preventing sliders which have transferred needles to the first carrier from beingV controlled by said means for causing the formation of stitches until they have again become associated with needles.

8. A knitting machine comprising superposed needle carriers, sliders provided With butts and needles controlled by the sliders movable in said carriers, means for transferring all needles located in one carrier to the other carrier, means for thereafter transferring selected needles from the second carrier to the first carrier, means for controlling sliders in the second carrier to cause needles therein to form stitches, and means appurtenant to each of two feeding stations for preventing sliders which have transferred needles to the first carrier from being controlled by said means for causing the formation of stitches.

9. A knitting machine comprising superposed needle carriers, sliders provided With butts and needles controlled by the sliders movable in said carriers, means for transferringV all needles lccated inone carrier to the other carrier, means for thereafter transferring selected needles from the second carrier to the first carrier, means for controlling sliders in the second carrier to cause needles therein to form selectively stitches of varying types, and means including at least one cam between the point of Yselective vtransfer and v1.6 the means for controlling kthe formation of stitches for preventing sliders which have transferred needles to the first carrier from being controlled by said means for causing the formation of stitches I 10. A knitting machine comprising superposed needle carriers, double-ended needles mounted in said carriers, sliders in both carriers arranged to control movements of said needles, means "for transferring needles from sliders in one carrier to sliders in the other, means for retransferring needles from sliders in the second mentionedcarrier to sliders in the first, means controlling sliders in the second carrier subsequent to the region of retransfer to cause needles controlled by them to form stitches, means controlling sliders in Vthe first carrier subsequent to the region of retransfer to cause needles controlled by them to form stitches, said means for controlling sliders in the second carrier selectively causing them to follow alternative paths to effect the forma' tion of different types of stitches, and means for controlling those sliders in the second carrier which have retransferred their needles so as to avoid action thereupon by the means for controlling sliders in the second carrier to form stitches.

11. A knitting machine comprising superposed y to sliders in the other, means for retransferring needles from sliders in the second mentioned carrier to sliders in the first, means controlling sliders in the second carrier subsequent to the region of retransfer to cause needles controlled by them to form stitches, means controlling sliders in the first carrier subsequent to the region of retransfer to cause needles controlled by them to form stitches, said means for controlling sliders in the second carrier selectively causing them to follow alternative paths to effect the formation of different types of stitches and leaving them in alternative positions in` at least one of which they would be incapable of receiving needles in a transfer operation'and, means for controlling those sliders in the second car-A rier which have retransferred their needles so as to avoid action thereupon by the means for controlling sliders in the secondcarrier to form stitches.

12.. A knitting machine comprising superposed needle carriers, double-ended needles mounted in said carriers, sliders in both carriers .arranged to control movements of said needles, means for transferring needles from sliders in one carrier to sliders in the other,v means for retransfe'rring needles from sliders in the second mentioned carrier to sliders in the first, means controlling sliders in the second carrier subsequent to the region of retransfer to cause needles controlled by them to form stitches, said means for controlling sliders in the second carrier selectively causing them to follow alternative paths to effect the formation of different types of stitches, and means-for controlling those sliders in the second carrier which have retransferred their needles so as to avoid actionthereupon by the means for controlling sliders in the second carrier to form stitches. K

13. A knitting machine comprising superposed needle carriers, double-ended needles mounted in said carriers, sliders in both carriers arranged to control movements of said needles, means for' transferring needles from sliders in one carrier to sliders in the other, means for retransferring needles from sliders in the second mentioned carrier to sliders in the iirst, means con.- trolling sliders in the second carrier subsequent to the region of retransfer to cause needles controlled by them to form stitches, said means for controlling sliders in the second carrier selectively causing them to follow alternative paths to effect the formation of different types of stitches and leaving them in alternative positions in at least one of which they would be incapable of receiving needles in a, transfer operation, and means for controlling those sliders in the second carrier whiclrhave retransferred their needles so as to avoid action thereupon by the means for controlling sliders in the second carrier to form stitches.

14. A knitting machine comprising superposed needle carriers, double-ended needles mounted in said carriers, sliders in both carriers arranged to control movements of said needles, means for transferring needles from sliders in one carrier to sliders in the other, means for retransferring needles from sliders in the second mentioned carrier to sliders in the rst, means controlling sliders in the second carrier subsequent to the region of retransfer to cause needles controlled by them to form stitches, said means for controlling sliders in the second carrier leaving them in a position in which they Would be incapable of receiving needles in a transfer operation, and means for controlling those sliders in the second carrier which have retransferred their needles so as to avoid action thereupon by the means for controlling sliders in the second carrier to form stitches.

15. A knitting machine comprising superposed needle carriers, double-ended needles mounted in said carriers, sliders in both carriers arranged to control movements of said needles, and a plurality of successive control phases, each of said phases including means for transferring needles from sliders in one carrier tol sliders in the other, means for retransferring needles fom sliders in the second mentioned carrier to sliders in the rst, means controlling sliders in the second carrier` subsequent to the region of retransfer to cause needles controlled by them to form stitches, said means for controlling sliders in the second carrier leaving them in a position in which they would be incapable of receiving needles in a subsequent transfer operation, and means for controlling those sliders in the second carrier which have retransferred their needles so as to avoid action thereupon by the means for controlling sliders in the second carrier to form stitches.

16. A knitting machine comprising superposed 18 needle carriers, double-ended needles mounted in said carriers, sliders in both carriers arranged to control movements of said needles, and a plurality of successive control phases, each of said phases including means for transferring needles from sliders in one carrier to sliders in the other, means for retransferring needles from sliders in the second mentioned carrier to sliders in the first, means controlling sliders in the second carrier subsequent to the region of retransfer to cause needles controlled by them to form stitches, said means for controlling sliders in the second carrier selectively causing them to follow alternative paths to effect the formation of different types of stitches and leaving them in alternative positions in at least one of which they would be incapable of receiving needles in a subsequent transfer operation, and vmeans for controlling Athose sliders in the second carrier which have retransferred their needles so as to avoid action thereupon by the means for controlling sliders in the second carrier to form stitches.

17. A knitting machine comprising superposed needle carriers, double-ended needles mounted in said carriers, sliders in both carriers arranged to control movements of said needles, means for effecting transfer of needles from sliders in one carrier to companion sliders in the other, the sliders in one carrier, when their companion needles are associated with sliders in the other carrier, not being retracted by a knitting cam, and supplemental means for reti-acting such sliders at the knitting point so that they Will not interfer@ with the knitting of stitches by their companion needles operating in the other carrier.

18. The method of controlling sliders in a knitting machine comprising superposed needle carriers, double-ended needles mounted therein, sliders in both carriers for controlling the needles, and means for controlling sliders to transfer needles and cause needles to form stitches, which comprises causing empty sliders of one carrier to travel past the region of formation of stitches in a special path to insure their proper location to receive needles in a transfer operation.

19. The method of controlling sliders in a knitting machine comprising superposed needle carriers, double-ended needles mounted therein, sliders in both carriers for controlling the needles, and means for controlling sliders to transfer needles and cause needles to form stitches, which comprises effecting selection of sliders to alternative positions, and causing all empty sliders of at least one of the carriers to occupy a position to receive needles at the location of transfer regardless of any previous selection of sliders.

PAUL W. BRISTOW. 

